Vehicles typically include tanks for carrying quantities of fluids needed for their operation. For example, a typical harvester may include a tank for carrying a supply of diesel fuel used to operate a diesel engine. Even in larger vehicles such as harvesters, however, space for onboard fluid tanks is often limited by the other system components. As such, complex tank geometries are often desired in order to maximize tank capacity in a given space. Plastic tanks are often used, owing to the more complex yet economical geometries they provide. Plastic tanks, however, are often exposed to heat sources and combustible materials, such as high temperature vehicle components and hot fluids, as well as debris and other materials which may compromise their integrity. Plastic tanks are also susceptible to expansion due to, for example, hydrostatic pressure and permeation from the fluids they contain, as well as thermal expansion and fluid sloshing caused by external components and vehicle dynamics. Some vehicles include partial coverings, such as formed heat shields, to protect the integrity of their fuel tanks. Partial coverings, however, provide only partial protection from heat sources and harmful materials. Formed heat shields are overly complex to install, are not conducive to covering tanks having complex geometries, and may allow debris and other materials to infiltrate the area between the heat shield and tank.